I use a temporary mobile HF setup on my Caravan when I go on vacations. I use a 2 by 4 board that has holes drilled at the ends to allow U bolts to pass through. The U bolts
are used to hold the board to the roof rack side rails. On the board, I mounted 2 ball
mounts and SO239 connectors to allow the 2 coax cables to connect rapidly to the 2
antennas. I use 2 Hustler MO4 masts (the short ones), each with a 3 resonator adapter.
I use 3 Hustler resonators on each mast which allows for 6 band coverage, in my case,
10, 12, 15, 17, 20, and 40 meters. I run the 2 coax cables into the Caravan and use
the antenna switch of my MFJ tuner to switch. I also use the Hustler quick disconnect
adapters for the masts. If you mount the ball mounts at the end of the board, you
should have enough clearance between resonators so they don't hit each other.
To provide a ground connection at the SO239 connector, I have tried running a wire
between the 2 connectors and the chassis of the van and used a C-clamp type of ground
connector that you can get for conduit. You could also drill a hole to connect the
wire, but I have never done that. This scheme worked but I was having too many RF
bites so I am now using a wire connected to an old mag mount base from an old 2 meter antenna and use the capacitive coupling. It seems to work great. I use this mag mount
setup for each ball mount.
An alternative to using the board is to use one roof top carrier that you can get at
the auto parts stores.
I also mount the radio and tuner (I have fine tuned the antennas, so the tuner just
helps keep things tame) on a board setup (looks like an upside down T) that has mobile
mounts installed. The board slides between the 2 front seats. The only thing left
permanent is the DC power cable (which I curl up and hide when not used).
I have used both the Kenwood TS130s and TS140s mobile.
